Photo-Induced Metastable Effects in Hydrogenated Amorphous Silicon (a-Si:H)

Light induced changes of electronic properties are studied in glow discharge deposited a-Si: H-films by ESR, field effect, DLTS and electronic transport. These effects are caused by silicon dangling bonds generated by recombination processes, which raise the density of states near midgap. The concomitant increase of potential fluctuations indicates that these defects are inhomogeneously distributed.